Miniature Direct-Conversion Transceiver

A flexible miniature digital transceiver based on unique architectures is proposed for direct digital synthesis and data conversion of radio frequency (RF) wireless spectrums without intermediate frequency (IF) stages. The transceiver combines innovative direct-conversion analog-to-digital and digital-to-analog converters (ADCs/DACs) with a novel sample rate converter (SRC). A 25 MHx signal bandwidth centered at up to 2 GHx can be generated or received directly from baseband inphase/quadrature (I/Q) digital data without analog IF conversion stages. The transceiver targets communication efforts for ARPA's multiband, multimode radio (Speakeasy); simultaneous video, voice, and data communications for multimedia applications (Future Digital Radio (FDR)); and satellite commnications (Global Positioning System (GPS)), direct broadcast satellite (DBS), etc.). It will benefit current transceivers in cellular phones and personal communication systems (PCS) by replacing loosy analog RF components with exact, reliable digital signal processing. It also targets low-power, low-cost, small form factor radios. During Phase I the transceiver's architecture will be defined, partitioned, and simulated. In phase II the key circuits will be designed, fabricated, and tested. Government and commercial customers have been identified and additional parners will be sought throughout the development cycle to ensure a successful manufactruing and marketing venture. Anticipated Military Benefits/Potential Commercial Applications of the Research or Development: The flexible digital transceiver will benefit wideband multimission military communications in the battlefield, including small form factor radios and multi-media communications using laptop computers. Commercial wireless industries such as cellular phones, personal communications systems, and wide area networks (WAN) will see a dramatic improvement in performance and flexibility, and reduction in power, cost and size.